Re: [Harp-L] Comb Design

[Joe Leone <3n037@xxxxxxxxxxx>]

On May 20, 2011, at 11:05 AM, Derwood wrote:

> Let me start by saying my opinion of the comb tone debate is that the comb
> material effects the vibrations that the player experiences and has the most
> effect on how the sound feels to the player.

I feel the same way. 

> I tend to prefer to play more solid combs. So that leads to my question,

I prefer my solid bronze 270. Most of my other chromatic combs are still wood. (diatonics all spl-20s) 
> 
> Why do manufacturers make plastic combs with hollow sections.

When molding plastic, the cooling would be different for thinner sections than it is for thicker sections. This would cause shrinking that would pull the comb out of shape. So, the moldings have to be designed so that no cross section is thicker than the webs between the reed chambers (generally the thinnest part). That way the entire comb would cool evenly and hence keep it's shape. A metal comb is usually machined and has no such limitation. However MY metal comb does have areas cut out in an effort to keep the weight down. The voids are also a handy place to stash gems. 

> Is it for some perceived tonal effect,

No

> to reduce weight

No

> or is it to save money on plastic
> material?

No, the plastic is only worth a penny and the mold for those channels is FAR more expensive than without the channels. 
> 
> Since I seem (have not yet done a double blind) to like the vibration of
> solid wood and aluminum combs, I wounder if a solid plastic comb would be
> more pleasing to me than the standard "thinline" plastic combs.

I don't know but the Amadeus chromatic has a fairly solid comb (lucite) and I love the sound. For diatonics, I don't think it would matter. They are already so 'vocal' that I don't think they can be improved upon. 
> 
> Any thoughts? Any real knowledge of manufacturers motives?

Motives are: Plastic is more stable than wood. Metal is too heavy for some applications. Moulding (once a mold is made) is cheaper than milling plastic. 
smo-joe


> 
> Thanks,
> 
> Derwood